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How a hawk learned to use traffic signals to hunt more successfully

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Re: How a hawk learned to use traffic signals to hunt more successfully

#41

Post by throwanem »

im3w1l wrote: post #39
vikingerik wrote: post #32

Earlier quoted context omitted.

Well, there is survivor bias there, of course; you don't see the ones that didn't learn to dodge...

But it makes you wonder why they cut it that close. What benefit they get from it. I can think of several plausible reasons but none that is self-evidently true.

Why waste energy giving someone else a free shot at whatever you're finding it worth your time to stand in the street over? It isn't that someone else wants that dropped french fry or whatever. It's that everyone else does.

Re: How a hawk learned to use traffic signals to hunt more successfully

#42

Post by morkalork »

vidarh wrote: post #36
hackeraccount wrote: post #28

Earlier quoted context omitted.

There are Peregrine falcons in my city. I remember walking downtown one time and seeing one on the sidewalk with a pigeon in its talons. All the commuters and I just walked around it. Really weird somehow.

London apparently has a high density of them (but high density still only means something like 40 breeding pairs), and some people are all excited about the prospect that they can do something about the rapidly rising wild parakeet population...

I'm having a hard time squaring away the image of grey gloomy London also being overrun with colourful tropical looking birds, I had to google it and see.

Re: How a hawk learned to use traffic signals to hunt more successfully

#43

Post by throwanem »

vikingerik wrote: post #32
throwanem wrote: post #30

Earlier quoted context omitted.

I see pigeons and sparrows dodge cars by inches, too. For that matter I do the same myself! Sparrows hawk insects out of the air, and I believe starlings also. Predicting motion would need to be second nature, I think. Like skillfully catching a ball, but much more so and between your teeth...

Well, there is survivor bias there, of course; you don't see the ones that didn't learn to dodge...

Correct. They would be visibly laminated to the pavement or smashed in the gutter. It does happen, but less often than ospreys drop fish in late summer.

Re: How a hawk learned to use traffic signals to hunt more successfully

#44

Post by blarg1 »

throwanem wrote: post #30
krisoft wrote: post #6

I have a similar story. I was taxiing a Cessna 152 at LHBS. It is a big grassy field. On that day there were a large flock of black birds sitting on the grass. I made the usual radio call to announce that I'm leaving the runway and taxiing to the tie-downs when the birds flitted away just between my airplane's nose and my destination. The birds outside of that "road" by roughly a wingspan distance remained on the gro…

I see pigeons and sparrows dodge cars by inches, too. For that matter I do the same myself! Sparrows hawk insects out of the air, and I believe starlings also. Predicting motion would need to be second nature, I think. Like skillfully catching a ball, but much more so and between your teeth...

I once threw a tennis ball straight up, just as a bird happened to be flying past, it rolled right and dodged it by a cm.

Re: How a hawk learned to use traffic signals to hunt more successfully

#45

Post by morkalork »

Etheryte wrote: post #15
lloeki wrote: post #13

> Cooper’s hawk is on a rather short list of bird of prey species that have successfully adapted to life in cities. A city is a difficult and very dangerous habitat for any bird, but particularly for a large raptor specializing in live prey: you have to avoid windows, cars, utility wires, and countless other dangers while catching something to eat every day. Peregrine falcons adapted quite well, and they're much more…

Plus pigeons are not exactly known for being incredibly smart or agile, so if you're big enough to take one down, you probably won't struggle too much for food.

Except for the part where pigeon racing is an entire sport that relies on both their speed and intelligence

Re: How a hawk learned to use traffic signals to hunt more successfully

#46

Post by throwanem »

blarg1 wrote: post #44
throwanem wrote: post #30

Earlier quoted context omitted.

I see pigeons and sparrows dodge cars by inches, too. For that matter I do the same myself! Sparrows hawk insects out of the air, and I believe starlings also. Predicting motion would need to be second nature, I think. Like skillfully catching a ball, but much more so and between your teeth...

I once threw a tennis ball straight up, just as a bird happened to be flying past, it rolled right and dodged it by a cm.

I don't really know what it's like to be a bird, of course, but I have to imagine their subjective experience of duration differs greatly from ours.

Re: How a hawk learned to use traffic signals to hunt more successfully

#47

Post by glxxyz »

lloeki wrote: post #35
hackeraccount wrote: post #28

Earlier quoted context omitted.

There are Peregrine falcons in my city. I remember walking downtown one time and seeing one on the sidewalk with a pigeon in its talons. All the commuters and I just walked around it. Really weird somehow.

Interesting, around here raptors hunt high, and if prey falls to the ground they abandon it; too dangerous to go down in the streets.

I almost ran one over turning in a car park in Edmonton. Backed up and it was still standing on the pigeon glaring at me. I drove around.

Re: How a hawk learned to use traffic signals to hunt more successfully

#48

Post by throwanem »

lloeki wrote: post #34
throwanem wrote: post #25

Earlier quoted context omitted.

Peregrines are somewhat smaller and much more lightly built. I live in a nesting pair's territory which often sees transitory Cooper's; they're easy to distinguish both in flight and at rest. Male Cooper's are more peregrine-sized and hard to tell from sharp-shinned hawks sometimes, but that is an ordinary enough sexual dimorphism in birds. Interestingly, while peregrines and accipiters like Cooper's share a habit of…

Sadly we don't have Cooper's around here so I have no experience with them, hence why I looked them up (see nearby comment) and according to that source found out they were on the smaller size and much smaller weight. Around here the only ones who would dare mob a peregrine would be crows.

Sure. I'm just talking about the impression they give in life. But I suppose in that sense the other birds must find a peregrine much more striking, and it very belatedly occurs to me that peregrines no doubt look smaller and more gracile to me for the higher altitudes their stooping hunting habit would require. When I do occasionally see them on approach to their nearby nest, I'm struck by their relative size. So yeah, between that and reviewing my Sibley's the error here is mine, though - for that matter, likely also because - I do find all falcons rather streamlined and compact in impression compared with accipiters or buteos.

Re: How a hawk learned to use traffic signals to hunt more successfully

#50

Post by devoutsalsa »

I once wrote a personal’s ad in SQL on Craigslist, back when they had that section. A DBA replied and asked if I wanted hawking. She had a Cooper’s hawk. I met her at a commercial park in a Saturday morning. She was driving a Honda CRV, the hawk was in the front passenger seat, and I hopped into the back seat.

She started driving and spotted some crows. The hawk saw them as well. Wearing a “don’t kill me either your claws” glove, she moved her hand to the hawk, who gleefully jumped on. She rolled down her window, stuck the hawk outside, and it was basically a drive by shooting with a bird bullet. This happened three times.

My most vivid memory of this was her ripping the crows apart into pieces and putting the then into a bucket, like it was sushi you’d order from KFC.

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